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CHAPTER 7 8-BIT TIMER/EVENT COUNTERS 50 AND 51
Preliminary User’s Manual U16035EJ1V0UM
Figure 7-4. Format of Timer Clock Select Register 51 (TCL51)
Address: FF79H After reset: 00H R/W
Symbol
7
6
5
4
3
2
1
0
TCL51
0
0
0
0
0
TCL512
TCL511
TCL510
TCL512
TCL511
TCL510
Count clock selection
0
0
0
TI51 falling edge
0
0
1
TI51 rising edge
0
1
0
f
X
/2 (4.19 MHz)
0
1
1
f
X
/2
3
(1.04 MHz)
1
0
0
f
X
/2
5
(261 kHz)
1
0
1
f
X
/2
7
(65.4 kHz)
1
1
0
f
X
/2
9
(16.3 kHz)
1
1
1
f
X
/2
11
(4.09 kHz)
Cautions 1. When rewriting TCL51 to other data, stop the timer operation beforehand.
2. Be sure to set bits 3 to 7 to 0.
Remarks 1.
When cascade connection is used, the settings of TCL5n0 to TCL5n2 (n = 0, 1) are valid only for
the lowermost timer.
2.
f
X
: Main system clock oscillation frequency
3.
Figures in parentheses are for operation with f
X
= 8.38 MHz
(2) 8-bit timer mode control register 5n (TMC5n: n = 0, 1)
TMC5n is a register which sets up the following six types.
<1>
8-bit timer counter 5n (TM5n) count operation control
<2>
8-bit timer counter 5n (TM5n) operating mode selection
<3>
Single mode/cascade connection mode selection
<4>
Timer output F/F (flip flop) status setting
<5>
Active level selection in timer F/F control or PWM (free-running) mode
<6>
Timer output control
TMC5n is set by a 1-bit or 8-bit memory manipulation instruction.
RESET input sets TMC5n to 00H.
Figure 7-5 shows the TMC5n format.